A way to get more variety using existing terrain tools would be different color varieties. Lighter and darker tones to terrain brushes, trees, rocks, even the water brush.
Agreed! I'd love a red clay/ red soil option, a dark brown dirt brush. Maybe water brushes with plants in them, murky water or agitated (active) water.
Before they add more terrain painting options they should extend the existing ones to all the maps. They added sand to Nublar when it wasn't available originally so I see no reason why both sand and shale can't be added to every map so we at least have options of how we want to paint the ground.